’99.9.21
Li-Ion BATTERY PROTECTOR
R5421NxxxC/xxxF series
s
OUTLINE
The R5421NxxxC/F Series are protection ICs for over-charge/discharge of rechargeable one-cell Lithium-ion (Li+) excess load
current, further include a short circuit protector for preventing large external short circuit current.
Each of these ICs is composed of three voltage detectors, a reference unit, a delay circuit, a short circuit protector, and a logic
circuit. When charging voltage crosses the detector threshold from a low value to a value higher than V
DET1
, the output of C
OUT
pin, the output of over-charge detector/VD1, switches to low level, charger's negative pin level. After detecting over-charge the
VD1 can be reset and the output of C
OUT
becomes high when the V
DD
voltage is coming down to a level lower than “V
REL1
”, or
when a kind of loading is connected to V
DD
after a charger is disconnected from the battery pack while the V
DD
level is in
between “V
DET1
” and “V
REL1
” in the R5421NxxxC/F version.
The output of D
OUT
pin, the output of over-discharge detector/VD2, switches to low level after internally fixed delay time
passed, when discharging voltage crosses the detector threshold from a high value to a value lower than V
DET2
.
After R5421NxxxC/F Series detect the over-discharge voltage, connect a charger to the battery pack, and when the battery
supply voltage becomes higher than the over-discharge detector threshold, VD2 is released and the voltage of D
OUT
becomes
“H” level. In the case of F version, after detecting the over-discharge detection, when the battery supply voltage becomes
equal or higher than over-discharge released voltage, VD2 is also released by the condition, and the voltage of D
OUT
becomes
“H” level.
An excess load current can be sensed and cut off after internally fixed delay time passed through the built in excess current
detector, VD3, with D
OUT
being enabled to low level. Once after detecting excess current, the VD3 is released and D
OUT
level
switches to high by detaching a battery pack from a load system.
Further, short circuit protector makes D
OUT
level to low immediately with external short circuit current and removing external
short circuit leads D
OUT
level to high. After detecting over-discharge, supply current will be kept extremely low by halt some
internal circuits operation. The output delay of over-charge detectors can be set by connecting external capacitors. Output type
of C
OUT
and D
OUT
are CMOS. 6-pin, SOT23-6 is available.
s
FEATURES
Low supply current....................................................Supply current
Standby current (detecting over-discharge)
Typ. 3.0µA
Typ. 0.3µA
(for R5421NxxxC)
Typ. 1.0µA
(for R5421NxxxF)
High accuracy detector threshold ..............................Over-charge detector (Topt=25°C)
±25mV
(Topt=0 to 50°C)
±30 mV
Over-discharge detector
±2.5%
Variety of detector threshold .....................................Over-charge detector threshold
4.0V - 4.4V step of 0.005V
Over-discharge detector threshold
2.0V - 3.0V step of 0.005V
Built-in protection circuit ..........................................Excess current protection
0.05V - 0.4V step of 0.005V
Accuracy
±15%
Output delay of over-charge ......................................Time delay at C3=0.01µF and V
DD
=4.3V
75ms for R5421N111C
Output delay of over-discharge .................................V
DD
=2.4V with built-in capacitor
10ms for R5421N111C/112C
Small package............................................................SOT-23-6 / 6-pin
s
APPLICATIONS
Li+ one-cell protector for battery pack
High precision protectors for cell-phones and any other gadgets using on board Li+ one-cell battery
Rev.1.11
-1-
s
BLOCK DIAGRAM
R5421NxxxC
5
V
DD
4
Ct
Level
Shifter
VD1
Delay
VD2
Short circuit
Detector
VD3
6
V
SS
1
D
OUT
3
C
OUT
2
V-
R5421NxxxF
5
V
DD
4
Ct
Level
Shifter
VD1
Delay
VD2
Short circuit
Detector
VD3
6
V
SS
1
D
OUT
3
C
OUT
2
V-
Rev.1.11
-2-
s
SELECTION GUIDE
In the R5421Nxxxx Series three of the input threshold for over-charge, over-discharge and excess current detectors can be
designated.
Part Number is designated as follows:
R5421N XXXX-XX
←Part
Number
↑ ↑ ↑
a b c
Code
a
b
c
Description
Serial Number for the R5421N Series designating input threshold for over-charge, over-discharge
and excess current detectors as well as hysteresis range for over-charge detector.
Designation of version symbols
Taping Type: TR (refer to Taping Specification)
s
PIN CONFIGURATION
6
5
4
(mark side)
1
2
3
s
PIN DESCRIPTION
Pin No.
1
2
3
4
5
6
Symbol
D
OUT
V-
C
OUT
Ct
V
DD
V
SS
Pin description
Output of over-discharge
detection, CMOS output
Pin for charger negative input
Output of over-charge
detection, CMOS output
Pin for external capacitor
setting output delay of VD1
Power supply
Ground
Rev.1.11
-3-
s
ABSOLUTE MAXIMUM RATINGS
Symbol
V
DD
V-
VCt
VC
OUT
VD
OUT
P
D
Topt
Tstg
Item
Supply voltage
Input Voltage
V - pin
Ct pin
Output voltage
C
OUT
pin
D
OUT
pin
Power dissipation
Operating temperature
range
Storage temperature range
Ratings
-0.3 to 12
V
DD
-28 to V
DD
+0.3
V
SS
-0.3 to V
DD
+0.3
V
DD
-28 to V
DD
+0.3
V
SS
-0.3 to V
DD
+0.3
150
-40 to 85
-55 to 125
V
SS
=0V
Unit
V
V
V
V
V
mW
°C
°C
ABSOLUTE MAXIMUM RATINGS
Absolute Maximum ratings are threshold limit values that must not be exceeded ever for an instant under any conditions.
Moreover, such values for any two items must not be reached simultaneously. Operation above these absolute maximum
ratings may cause degradation or permanent damage to the device. These are stress ratings only and do not necessarily
imply functional operation below these limits.
Rev.1.11
-4-
s
ELECTRICAL CHARACTERISTIC
q
R5421N111C
Symbol
Item
V
DD1
Operating input voltage
Minimum operating
Vst
Voltage for 0V charging
V
DET1
Over-charge threshold
Conditions
Voltage defined as V
DD
- V
SS
Voltage defined as V
DD
- V- ,
V
DD
- V
SS
=0V
Detect rising edge of supply
voltage
(Topt=25°C)
(Topt=0 to 50°C)
*Note
MIN.
1.5
TYP.
Topt=25°C
MAX.
Unit
10
V
1.2
V
4.225
4.220
4.00
4.250
4.250
4.05
75
2.500
10
0.20
4.275
4.280
4.10
90
2.563
13
0.23
V
V
V
ms
V
ms
V
V
REL1
tV
DET1
V
DET2
tV
DET2
V
DET3
tV
DET3
Release voltage for over-
charge detection
Output delay of over-
Charge
Over-discharge threshold
Output delay of over-
Discharge
Excess current threshold
C3=0.01µF, V
DD
=3.6V to 4.3V
Detect falling edge of supply
voltage
V
DD
=3.6V to 2.4V
Detect rising edge of 'V-' pin
voltage
60
2.437
7
0.17
Output delay of excess
V
DD
=3.0V
9
13
17
ms
Current
Vshort
Short protection voltage
V
DD
=3.0V
V
DD
-1.2 V
DD
-0.9 V
DD
-0.6
V
Output Delay of Short
tshort
V
DD
=3.0V
5
50
µs
protection
Reset resistance for Excess
Rshort
V
DD
=3.6V, V- =1.0V
50
100
150
kΩ
current protection
Vol1
Nch ON voltage of C
OUT
Iol=50µA, V
DD
=4.4V
0.35
0.5
V
Voh1
Pch ON voltage of C
OUT
Ioh=-50µA, V
DD
=3.9V
3.4
3.7
V
Vol2
Nch ON voltage of D
OUT
Iol=50µA, V
DD
=2.4V
0.2
0.5
V
Voh2
Pch ON voltage of D
OUT
Ioh=-50µA, V
DD
=3.9V
3.4
3.7
V
I
DD
Supply current
V
DD
=3.9V, V- =0V
3.0
6.0
µA
Istandby
Standby current
V
DD
=2.0V
0.3
0.6
µA
*Note: Considering of variation in process parameters, we compensate for this characteristic related to temperature by laser-
trim, however, this specification is guaranteed by design, not production tested.
Rev.1.11
-5-
嵌入式系统
